This visualization presents a scatterplot matrix of the Iris dataset, showing pairwise relationships among sepal length, sepal width, petal length, and petal width. The diagonal cells display histograms of each variable, with colored overlays accumulated by species. The code uses d3.csv for data loading, d3.scalePoint for positioning subplots, and d3.histogram to bin values. Points are colored by species using custom hex codes, while axis labels and ticks are rendered via d3.axisBottom and d3.axisLeft. The SVG canvas is sized to the window and centered with a flexbox container.